In recent decades, the laws of the United States, United
Kingdom, and many other nations have affirmed that people with mental disorder
have the right to give or withhold consent for their treatment. Only if
their decision-making abilities are seriously impaired may they be declared
legally incompetent to make such decisions, which then will be made for
them by courts or others appointed to decide on their behalf.

Little has been known, however, about the extent to which
mental disorders may impair people's abilities to make treatment decisions.
To the extent that they do, two concerns are raised. One is the danger
that some people's poor decisionmaking abilities may cause them to refuse
treatments that they need and that they would have wished to obtain if
they had had the capacity to comprehend the treatment's benefits. The other
concern is that disabilities in decision-making might cause some people
to accept certain treatments that they might otherwise refuse if they were
capable of comprehending the treatment's implications.

In the absence of reliable information, some professionals
and policy makers have claimed that mental disorders invariably impair
decisionmaking sufficiently to consider people with mental disorder legally
incompetent to make treatment decisions. Some patient advocates, on the
other hand, have argued that people with mental disorders are as capable
as people without them to make legally enforceable treatment decisions.

The MacArthur Treatment Competence Study, supported by the
Research Network on Mental Health and the Law of the John D. and Catherine
T. MacArthur Foundation, was designed to provide information to
policy makers and clinicians to help them address questions about the decision-making
capacities of people who are hospitalized with mental illness.
During its initial phase, beginning in 1988, the project developed interview
procedures to measure abilities that the legal system has identified as
relevant to decisionmaking competence. The four legally-relevant abilities
that we addressed were the abilities to state a choice, to understand
relevant information, to appreciate the nature of one's own situation,
and to reason with information.

Following this pilot testing, the full-scale study was conducted
with 498 participants recruited from three sites: Worcester, MA, Pittsburgh,
PA, and Kansas City, MO. These included several groups: patients recently
hospitalized with mental illness (either schizophrenia or major depression)
or medical illness (ischemic heart disease: "unstable angina");
and non-patients recruited from the community for comparison purposes.
Patients' decisionmaking abilities were assessed between two to seven days
after their admission to hospitals.

Results

The following findings were among the study’s most
important results:

Patients hospitalized with mental illness more often
showed deficits in their decisionmaking performance compared with
hospitalized medically ill patients and non-patient control groups. This
was especially true for patients hospitalized with schizophrenia, and to
a lesser extent for patients with depression.

Nevertheless, the majority of patients hospitalized
with schizophrenia performed adequately on any particular measure of decisionmaking
ability, and about half did well on all the measures combined. When patients
with schizophrenia performed poorly, they usually had more severe psychiatric
symptoms, especially disturbances of thought and perception (e.g.,
disorganized thinking and delusions). In contrast, decisionmaking performance
was not associated with simple demographic variables (e.g., age, gender,
race) or other mental status variables (e.g., degree of anxiety).

Patients hospitalized with depression showed intermediate
levels of decisionmaking performance, with about three-quarters performing
well on all measures combined. Patients with more severe depression did
not necessarily perform more poorly than those with less serious depression.

Medically ill patients, though hospitalized with a
potentially life-threatening condition, performed about as well as healthy
persons in the community, although a small proportion of these patients
did show some decisionmaking deficits.

When patients hospitalized for schizophrenia were
retested after a two-week period of treatment, substantial improvement
in decisionmaking abilities was observed for patients whose psychiatric
symptoms had decreased in severity.

Our measures of decisionmaking abilities were found
to be easy to administer and could be scored comparably by different raters.
They appeared to give valid indications of the degree of impairment in
participants' decisionmaking.

Implications

These results have several important implications for policy
makers and clinicians:

Most patients hospitalized with serious mental
illness have abilities similar to persons without mental illness
for making treatment decisions. Taken by itself, mental
illness does not invariably impair decisionmaking capacities. On
the other hand, a substantial percentage of hospitalized patients--up to
half in the group with schizophrenia when all four types of abilities
are considered--show high levels of impairment.

Future policy must take both these sets of findings
into account when determining whether hospitalized patients should
be allowed to make their own decisions about treatment.
Our results clearly do not support a policy that denies to patients
hospitalized with mental illness, on a blanket basis, the right
to consent to or refuse treatment. Nor do they support the view
that mental disorder has no effect on a person's decisionmaking
abilities.

Our results are consistent with systematic screening
of patients at high risk for impaired decisionmaking, a practice
that is not usually done in most hospitals. Routine screening
could identify patients who need added help in making treatment decisions
(e.g., making special efforts to inform them of the benefits and
risks of alternative treatments), and who need special review of their
decisions by doctors, family, or courts to protect them from decisions
they might make that could endanger their lives or welfare.

Our results are consistent with the view that
for many patients hospitalized with mental disorders, impairments
in decisionmaking ability are temporary and improve with treatment.
Patients with schizophrenia whose decisionmaking abilities seem
impaired early in their hospital stay may be more capable of making decisions
about continued treatment at a later time in their hospitalization.
By the same token, some patients in our study who appeared capable
of making treatment decisions a few days after their hospital admission
might have been less capable at the time that admission decisions
were made.

Whether patients are seen as legally competent
or incompetent to make their own decisions will depend on which
legal tests for decisionmaking competence are used in a particular jurisdiction.
An emphasis on one ability or another among the four that we examined
may exclude different groups of patients. Moreover, the more abilities
that are scrutinized, the greater will be the number of patients
considered incompetent.

Medical illness alone, even when associated with
the stress of hospitalization, appears rarely to impair treatment
decisionmaking.
Thus, objections to obtaining informed consent from medical inpatients
appear to be groundless. This conclusion may be different for
patients whose illnesses or treatment affect their mental state, or who
have concurrent mental disorders, which was not the case for the participants
in our study.

During the final phase of the MacArthur Treatment Competence
Study, we developed and tested an easy-to-use interview for assessing
patients' decisionmaking abilities. Called the MacArthur Competence
Assessment Tool-Treatment (MacCAT-T), this procedure is flexible enough
to be applied by clinicians in day-to-day care of patients with varied
disorders, yet is sufficiently standardized to provide ratings of patients'
capacities of all four of the legally-relevant abilities examined in
the earlier research study. The manual for the MacCAT-T is now available
from: Professional
Resource Press, P.O. Box 15560, Sarasota, FL 15560 (1-800-443-3364;
www.prpress.com),
in addition to interview and rating forms and a demonstration videotape.

The format of the MacCAT-T has been adapted for the assessment
of decisionmaking capacity in other contexts, as well. The most frequently
used of these is the MacCAT-CR, designed to assess potential subjects'
capacities to consent to participation in clinical research. Preliminary
studies have indicated that considerable impairment may exist in subjects
with schizophrenia, but may be greatly ameliorated by special efforts
to convey the material needed for an acceptable consent. Moderately
depressed subjects, in contrast, have not demonstrated substantial impairment
with the instrument.

The MacCAT-CR is being used in many sites for screening
research subjects and for further investigation of subjects' capacities
to consent to research participation. It is also available from Professional
Resource Press.

Other versions of instruments based on the MacCAT format
have been developed, including measures for assessing the capacities
of persons to complete a health care proxy, to complete a psychiatric
advance directive, and to make decisions about continuing to drive
(especially relevant for the elderly).

(1) The Working Group responsible for conducting this
research consists of Paul S. Appelbaum, M.D., and Thomas Grisso, Ph.D.
Requests for further information should be sent to either author at
the Department of Psychiatry, University of Massachusetts Medical School,
Worcester, MA 01655 (e-mail: AppelbaP@ummhc.org; Thomas.Grisso@umassmed.edu).